On Tue, Feb 27, 2001 at 01:31:17PM -0500, MaD dUCK wrote: > > this is horrible and it basically means that console access to a linux > machine means root rights. there are two steps that any system console access to any machine regardless of OS means root rights. > administrator should take IMHO, and these are disabling floppy/cdrom > boots as well as setting a password on the bios, and setting lilo's > timeout to 0. don't set lilo's timeout to 0 that makes it a royal pain to recover the system if something goes wrong, you can't boot single user any more and such. there is a better solution: add to /etc/lilo.conf password=s3cr3t and to the default kernel image section: restricted this way the default kernel image will boot without a password but only if NO command line arguments are passed at the lilo prompt. if you just hit enter or linux with no arguments you boot fine. if you try linux init=/bin/sh or linux single or linux 5 you get a password prompt where you must enter the correct lilo password. for grub add: password s3cr3t then add `lock' to any backup kernel menu entries you have. (this way someone can't boot the previous kernel and take advantage of a security hole in it) then grub will only let you boot the default menu entry without modification and will not allow access to any grub commands unless the passwd is entered. then of course chmod 600 /etc/lilo.conf or chmod 600 /boot/grub/menu.lst > if this is all taken care off, then you can recover by enabling floppy > boot and rescueing that system. an attacker would have to open the > box and reset (or crack) the bios. or use the backdoor or backdoor password in the bios. (many of them have this unfortunatly) -- Ethan Benson http://www.alaska.net/~erbenson/
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